Numerous moulded-over articles are known in this area. Generally, to fix the moulded-over article to the moulded object, a trench or cavity defined by walls projecting from the base of the mould is formed at the base of the mould in which the foam is poured to form the moulded object, the moulded-over article being placed on the outer top edges of said walls before the foam is poured. A magnet is placed in the bottom of the cavity defined by the projecting walls and the top surface of the moulded-over article is provided with a rib of metallic resin which, by magnetic co-operation with the magnet, holds the article for moulding over on the top edges of the walls of the cavity or trench, in order thus to keep the moulded-over article in position during the pouring of the foam.
However, the pressure of the poured foam is considerable. It is therefore necessary to seal the interface between the bottom surface and the top edges of the walls to prevent the foam from infiltrating inside the cavity and fouling the hooks which extend from the bottom surface of the moulded-over article. Another procedure is to provide a protective cocoon for the hooks, which is withdrawn by peeling after the withdrawal of the moulded object with the article moulded there over. These hooks, in fact, once the moulded object has been withdrawn with the moulded-over article fixed, will enable, for example, a fabric to be fixed by means of loops, in order to cover the moulded object, which can, for example, be a motor vehicle seat cushion. Generally, the base of the moulded-over article is provided with two upwardly inclined ramps to enable the moulded-over article to be clipped between two side walls. Obviously this system is complicated and takes time, and this gives rise to problems in installations for the production of moulded objects, for example motor vehicle seats. It is of course possible to provide additional means, such as a pre-solidified layer of foam which prevents the liquid from penetrating into the cavity by compression of the pre-solidified foam. It is also possible to provide bottom lips extending from the bottom surface and surrounding the hooks in order to protect the foam. These protective lips are complicated to manufacture.